JP2009047250A - Electromagnetic clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic clutch capable of preventing generation of disagreeable noise when the clutch is operated without largely changing the design of a known clutch having no member for suppressing the vibration. <P>SOLUTION: The electromagnetic clutch 1 comprises a rotor 20 which is an input rotating body fixed to a rotary shaft 10 on the input side, a worm wheel 30 which is an output rotating body provided coaxial with the rotor 20 and provided in a relatively rotating manner to the rotary shaft 10, an armature 40 consisting of a magnetic body which is axially slidable to the rotor 20 side of the worm wheel 30 and mounted thereon in a non-rotational manner, and an excitation coil 50 arranged opposite to the armature 40 across the rotor 20. The rotor 20 comprises a disk part 21 orthogonal to the rotary shaft, and a cylindrical part 22 formed from an outer circumference of the disk part 21 parallel to the rotary shaft. A vibration absorbing member 60 is affixed to an end face of a fore end of the cylindrical part 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electromagnetic clutch that switches transmission and disconnection of rotational force from an input rotator to an output rotator by electromagnetic force, and more particularly to a configuration that can reduce the generation of noise during operation.

  The electromagnetic clutch includes a rotor that is an input rotating body that rotates integrally with a rotating shaft, a disk plate that is an output rotating body, and an armature made of a magnetic material that is slidable and non-rotatable in the axial direction on the disk plate. And an exciting coil for switching the transmission and cutting of the rotational force from the rotating shaft to the disk plate by applying an electromagnetic force to the armature and sliding it in the axial direction.

  The armature is formed of a metal such as iron because it needs to be a magnetic body, and the rotor is also formed of metal in order to ensure durability. For this reason, the vibration generated when the armature is attracted to the rotor and collides with the rotor is not attenuated, and the rotor is vibrated. Since the frequency of this vibration is generally several hundred to several kHz, a high operating sound called “Keen” that is uncomfortable for the human ear is generated.

  Patent Document 1 discloses a configuration in which a vibration suppressing member made of plastic or synthetic rubber is attached to an armature in order to suppress the occurrence of such operating noise and vibration.

JP, 2007-146971, A FIG. 1, FIG.

  However, in the configuration described in Patent Document 1 described above, it is necessary to bond a vibration suppression member having substantially the same diameter as the armature to the armature inside the clutch before assembling the clutch, and the conventional vibration suppression member is not provided. The design of the internal space and the manufacturing process are greatly different from the clutch, and there is a problem that the clutch of the conventional design cannot be used as it is.

  The present invention has been made in view of the above-described problems of the prior art, and is uncomfortable during clutch operation without greatly changing the design of a conventional clutch that does not include a member for suppressing vibration. It is an object of the present invention to provide an electromagnetic clutch capable of preventing noise generation.

  In order to achieve the above object, an electromagnetic clutch according to a first aspect of the present invention includes an input rotator, an output rotator provided coaxially with the input rotator and capable of relative rotation, and the input rotator and output rotator. And an armature made of a magnetic material that is slidable in the axial direction and non-rotatable in the rotational direction, and an electromagnetic force is applied to the armature to make the input rotator and output rotator And an excitation coil that switches between a transmission position for transmitting the rotational force by bringing the armature into contact with a rotating body that does not have an armature and a cutting position for separating the rotational force by separating the rotational force. The rotating body having no armature of the body and the output rotating body includes a disk portion perpendicular to the rotation axis and a cylindrical portion formed in parallel to the rotation axis from the outer periphery of the disk portion. Characterized in that the end face or the side face of the tip parts are stuck vibration absorbing member. In addition, a side peripheral surface means the internal peripheral surface or outer peripheral surface of a cylindrical part.

  According to a second aspect of the electromagnetic clutch, on the premise of the first aspect, a groove is formed along the circumferential direction on the end face of the tip of the cylindrical portion, and the vibration absorbing member is end faced by an adhesive filled in the groove. It is characterized by being affixed to.

  According to a third aspect of the electromagnetic clutch according to the first aspect, the end surface of the tip of the cylindrical portion is formed with a rough surface, and the vibration absorbing member is attached to the end surface with an adhesive adhered to the rough surface. It is characterized by being.

  The electromagnetic clutch according to claim 4 is based on the premise of claim 1 and the end surface of the tip of the cylindrical portion is formed in a taper shape, and the vibration absorbing member is attached to the end surface with an adhesive adhered to the taper surface. It is characterized by being.

According to the configuration of claim 1 described above, the vibration energy generated in the rotating body due to the collision with the armature during the clutch operation is converted into the thermal energy of the vibration absorbing member. However, it becomes a muffled sound with a low frequency, and it does not give people discomfort.
In addition, when the vibration absorbing member is attached to the end surface of the cylindrical portion of the rotating body that does not have an armature, this portion is not easily restricted by other parts such as a clutch cover, and the existing electromagnetic clutch The vibration absorbing member can be attached without changing the attachment state.

  On the other hand, when the vibration absorbing member is affixed to the outer peripheral surface of the cylindrical portion of the rotating body that does not have an armature, the adhesion area can be increased and the adhesive strength can be kept higher than when the vibration absorbing member is affixed to the end surface. Further, since the vibration absorbing member can be pasted after the clutch is assembled, there is an advantage that workability is good.

  Further, when the vibration absorbing member is attached to the inner peripheral surface of the cylindrical portion of the rotating body that does not have an armature, the adhesion area can be increased as compared with the case where the vibration absorbing member is attached to the end surface, and the adhesive force can be kept high. Furthermore, since the vibration absorbing member is not exposed to the outside, there is an advantage that the appearance of the clutch is not impaired.

  According to the configuration of claim 2 of the present application, the adhesive force is increased as compared with the case of attaching the vibration absorbing member without changing the shape of the end face, and the volume of the adhesive is increased by the amount of the groove, thereby absorbing Since the amount of vibration energy that can be (converted into thermal energy) is increased, the vibration absorption capability is increased, and therefore, the sound caused by vibration generated during clutch operation can be further reduced.

  According to the configuration of claim 3 of the present application, since the adhesive force is increased as compared with the case where the vibration absorbing member is attached without changing the shape of the end face, the vibration absorbing member is provided even when the vibration generated during the clutch operation is large. The sound caused by vibration can be reduced without peeling.

  According to the configuration of claim 4 of the present application, the adhesive area can be increased and the adhesive force can be kept high without greatly changing the end face of the tip of the cylindrical portion as in claim 2 or 3. Therefore, even when the vibration generated during the clutch operation is large, the vibration-absorbing member is not peeled off and the sound due to the vibration can be reduced.

  Embodiments of an electromagnetic clutch according to the present invention will be described below with reference to the drawings. Here, three embodiments having different attachment positions of the vibration absorbing member will be described in order.

  FIG. 1 is a partially longitudinal side view of the electromagnetic clutch 1 according to the first embodiment, FIG. 2 is a perspective view of the electromagnetic clutch shown in FIG. 1, and FIG. 3 is a perspective view showing only the rotor portion of FIG. is there.

  As shown in FIG. 1, the electromagnetic clutch 1 according to the first embodiment can rotate relative to the rotating shaft 10 coaxially with the rotor 20, which is an input rotating body fixed to the rotating shaft 10 on the input side. A worm wheel 30 that is an output rotating body provided on the armature 40 and an armature 40 made of a magnetic body that is slidable in the axial direction on the rotor 20 side of the worm wheel 30 and that is non-rotatable in the rotating direction. And an exciting coil 50 disposed opposite to the armature 40 with the rotor 20 interposed therebetween.

  The armature 40 is attached to either the input rotating body (rotor) or the output rotating body (worm wheel). In the first embodiment, the armature 40 is attached to the latter. Accordingly, the rotor 20 corresponds to “a rotating body having no armature”.

  The rotating shaft 10 is rotatably supported by two sets of bearings 11 and 12. One bearing 11 is fixed to a device to which the bearing is attached when the clutch is attached. The other bearing 12 is fixed to a yoke 51 that incorporates an exciting coil 50 and forms a magnetic path.

  As shown in FIGS. 2 and 3, the rotor 20 covers the disk portion 21 perpendicular to the rotation axis and covers the outer periphery of the yoke 51 in parallel with the rotation axis from the outer periphery of the disk portion 21. And a formed cylindrical portion 22. And the vibration absorption member 60 is affixed on the end surface of the front-end | tip of this cylindrical part 22. As shown in FIG. 2 and 3, the portion where the vibration absorbing member 60 is attached is indicated by hatching (this hatching is not a cross section).

In this example, the vibration absorbing member 60 is a resin such as rubber formed in a tape shape, and is affixed to the end surface with an adhesive.
The vibration absorbing member 60 only needs to be able to absorb vibration generated in the metal rotor 20, and is not limited to the tape-shaped rubber as described above, and may be cured by applying a resin paint.

The worm wheel 30 is mounted so as to be rotatable with respect to the rotary shaft 10, and is positioned between the rotor 20 fixed to the rotary shaft and the retaining ring 13 in the axial direction. On the outer periphery of the worm wheel 30, a worm gear 31 that meshes with a gear of a drive target device (not shown) is formed.
Further, on the rotor 20 side of the worm wheel 30, a protrusion 32 that protrudes toward the rotor 20 side is formed at an intermediate portion. The protrusion 32 engages with a positioning hole 41 formed in the armature 40, whereby the armature 40 is attached to the worm wheel 30 so as to be slidable and non-rotatable in the axial direction.
Note that a wave washer 23 is sandwiched between the rotor 20 and the armature 40, so that an elastic force in a direction away from the rotor 20 is constantly acting on the armature 40.

The exciting coil 50 is mounted inside the yoke 51 while being wound around the bobbin 53. Excitation current is supplied to the excitation coil 50 from the outside via the power cord 52. The operation of the electromagnetic clutch 1 is controlled by supplying and disconnecting current to the exciting coil 50.
That is, when a current is supplied to the exciting coil 50, the electromagnetic force generated by the current flowing through the exciting coil 50 acts on the armature 40 via the yoke 51, and resists the elastic force applied by the wave washer 23. 40 contacts the rotor 20, and the rotation of the rotor 20 is transmitted to the worm wheel 30 via the armature 40.
When the current supplied to the exciting coil 50 is cut off, the electromagnetic force acting on the armature 40 disappears, the armature 40 is separated from the rotor 20 by the elastic force of the wave washer 23, and the rotation of the rotor 20 is caused by the worm wheel 30. Is not communicated to.

  Thus, it is possible to switch between a transmission position where electromagnetic force is applied to the armature, the armature is brought into contact with the rotor to transmit the rotational force, and a cutting position where the rotational force is separated from the rotor to cut the rotational force. .

  With the operation of the electromagnetic clutch 1, especially when the armature 40 slides from the cutting position to the transmission position and collides with the rotor 20, vibration is generated in the rotor 20. This vibration energy is generated by the vibration absorbing member 60. It is converted to the thermal energy of the adhesive layer and greatly attenuates, so the volume of generated noise can be reduced and the frequency can be lowered, preventing the generation of high noise that is unpleasant to human ears it can.

Subsequently, a modification of the first embodiment will be described with reference to FIGS.
In the first embodiment, the vibration absorbing member 60 is attached to the end face of the tip of the cylindrical portion 22 of the rotor 20. However, it may be considered that the adhesive force is insufficient by simply attaching the vibration absorbing member 60. Therefore, in the modification, a device for increasing the adhesive force is incorporated.

  In the example of FIG. 4, a V-shaped groove 22a is formed on the tip surface of the cylindrical portion 22 of the rotor 20, and in the example of FIG. 5, a rectangular groove 22b is similarly formed on the tip surface. Adhesive force can be improved by injecting an adhesive into these groove portions and attaching the vibration absorbing member 60 shown in FIG.

  In the example of FIG. 6, the surface of the tip surface of the cylindrical portion 22 of the rotor 20 is formed as a rough surface 22c. By applying an adhesive to the rough surface 22c and attaching the vibration absorbing member 60 shown in FIG. 1, the adhesive force can be increased compared to applying the adhesive to a smooth surface.

  Further, in the example of FIG. 7, the end face at the tip of the cylindrical portion 22 of the rotor 20 is formed as a tapered surface 22d, and the vibration absorbing member 60 shown in FIG. 1 is attached to the tapered surface 22d. Thus, since the application area of an adhesive agent can be increased by making the end surface of the front-end | tip of the cylindrical part 22 into a taper shape, the adhesive force can be strengthened rather than apply | coating an adhesive agent to a perpendicular | vertical surface.

  FIG. 8 is a partially longitudinal side view of the electromagnetic clutch 2 according to the second embodiment of the present invention. The difference from the first embodiment shown in FIG. 1 is the attachment position of the vibration absorbing member 61. Since other configurations are the same as those of the first embodiment, the same members as those of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

As shown in FIG. 8, in the electromagnetic clutch 2 according to the second embodiment, a vibration absorbing member 61 is attached to the outer periphery of the cylindrical portion 22 of the rotor 20.
In this way, when the vibration absorbing member 61 is affixed to the outer peripheral surface of the cylindrical portion 22, the adhesion area can be increased compared to the case of the first embodiment, so that the adhesion force can be kept high.
Further, since the vibration absorbing member 61 can be attached after the clutch is assembled, there is an advantage that workability is good. However, the thickness of the vibration absorbing member 61 needs to be determined so as not to interfere with other parts such as a cover (not shown).

  FIG. 9 is a partially longitudinal side view of the electromagnetic clutch 3 according to the third embodiment of the present invention. The difference from the first embodiment shown in FIG. 1 is the attachment position of the vibration absorbing member 62 and the thickness in the direction perpendicular to the rotation axis of the cylindrical portion 22 and the yoke 51. Since other configurations are the same as those of the first embodiment, the same members as those of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 9, in the electromagnetic clutch 3 of the third embodiment, a vibration absorbing member 62 is attached to the inner periphery of the cylindrical portion 22 of the rotor 20. Accordingly, in order to secure a space for disposing the vibration absorbing member 62, the thickness of the cylindrical portion 22 to which the vibration absorbing member 62 is attached and the thickness of the yoke 51 facing this are made thinner than the configuration of the first embodiment. ing.

As described above, when the vibration absorbing member 62 is attached to the inner peripheral surface of the cylindrical portion 22, the adhesion area can be increased as compared with the case of the first embodiment, so that the adhesion force can be kept high.
Further, since the vibration absorbing member 62 is not exposed to the outside, there is an advantage that the appearance of the clutch is not impaired. However, there are cases where the design of some parts needs to be changed as described above. In addition, the thickness of the vibration absorbing member 62 needs to be determined so as not to interfere with surrounding components.

In each of the above embodiments, the vibration absorbing member is attached to one place. However, when the vibration absorbing effect is insufficient at only one place, the vibration absorbing member may be attached to a plurality of places.
For example, Example 1 and Example 2 may be combined and attached to two locations of the end surface and the outer peripheral surface of the cylindrical portion of the rotor, or a combination of the end surface and the inner peripheral surface, the outer peripheral surface and the inner peripheral surface, Furthermore, you may affix on three places, an end surface, an outer peripheral surface, and an inner peripheral surface.

It is a partial longitudinal cross-sectional side view of the electromagnetic clutch concerning Example 1 of this invention. It is a perspective view of the electromagnetic clutch shown in FIG. It is a perspective view which takes out and shows only the rotor part of FIG. 6 is a cross-sectional view of an end surface of a cylindrical portion of a rotor showing a first modification of Example 1. FIG. FIG. 6 is a cross-sectional view of an end surface of a cylindrical portion of a rotor showing a second modification of the first embodiment. 6 is a cross-sectional view of an end surface of a cylindrical portion of a rotor showing a third modification of Example 1. FIG. 6 is a cross-sectional view of an end surface of a cylindrical portion of a rotor showing a fourth modification of Example 1. FIG. It is a partial longitudinal cross-sectional side view of the electromagnetic clutch concerning Example 2 of this invention. It is a partial longitudinal cross-sectional side view of the electromagnetic clutch concerning Example 3 of this invention.

Explanation of symbols

1, 2, 3: Electromagnetic clutch 10: Rotating shaft 11, 12: Bearing 13: Retaining ring 20: Rotor 21: Disk portion 22: Cylindrical portion 22a: V-shaped groove 22b: Rectangular groove 22c: Rough surface 22d: Tapered surface 23 : Wave washer 30: Worm wheel 31: Worm gear 32: Protrusion 40: Armature 41: Positioning hole 50: Excitation coils 60, 61, 62: Vibration absorbing member

Claims (4)

An input rotator,
An output rotator provided coaxially with the input rotator so as to be relatively rotatable;
An armature made of a magnetic material attached to one of the input rotator and the output rotator so as to be slidable in the axial direction and not rotatable in the rotational direction;
An electromagnetic force is applied to the armature, and the armature is brought into contact with a rotating body that does not have the armature among the input rotating body and the output rotating body, and is separated from a transmission position that transmits the rotating force. And an exciting coil that switches between cutting positions for cutting the rotational force,
A rotating body having no armature out of the input rotating body and the output rotating body includes a disk portion perpendicular to the rotating shaft and a cylindrical portion formed in parallel to the rotating shaft from the outer periphery of the disk portion. An electromagnetic clutch, wherein a vibration absorbing member is attached to an end surface or a side peripheral surface at the tip of the cylindrical portion. A groove is formed in a circumferential direction on an end face of the tip of the cylindrical portion, and the vibration absorbing member is attached to the end face with an adhesive filled in the groove. Item 2. The electromagnetic clutch according to Item 1. The end surface of the tip of the cylindrical portion is formed with a rough surface, and the vibration absorbing member is attached to the end surface with an adhesive adhered to the rough surface. Electromagnetic clutch. The end surface of the tip of the cylindrical portion is formed in a taper shape, and the vibration absorbing member is attached to the end surface with an adhesive adhered to the taper surface. Electromagnetic clutch.

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